Monomer, polymers, and ophthalmic lenses and contact lenses made by using the same

ABSTRACT

A monomer as represented by general formula (a) or (a′) below, with which a polymer having high oxygen permeability and transparency and suited to an ophthalmic lens is obtained, is provided. Suitable monomers include: 
                         
wherein A is a siloxanyl group; R 1  is H or a methyl group; R 2  is a substituted group that is selected from the group consisting of alkyl groups with 1 to 20 carbon atoms that may be substituted, aryl groups with 6 to 20 carbon atoms that may be substituted and formula (c) below.

This is a filing under 35 U.S.C. 371 of PCT/JP02/02380 filed on Mar. 31,2002, claiming the benefit of JP 2001-100211, filed on Mar. 30, 2001.

TECHNICAL FIELD

This invention relates to monomers and polymers. Said monomers andpolymers are particularly suited to use for ophthalmic lenses such ascontact lenses, intraocular lenses and artificial corneas.

PRIOR OF ART

Conventionally, monomers containing silicon groups are known as monomersfor ophthalmic lenses. For example, 3-[tris(trimethylsiloxy)silyl]propylmethacrylate has been widely used as monomers for ophthalmic lenses.Polymers obtained by copolymerizing 3-[tris(trimethylsiloxy)silyl]propylmethacrylate with N,N-dimethylacrylamide, which is a hydrophilicmonomer, have the merits of being transparent and of having high oxygenpermeability. However, sufficient compatability is not obtained withthree component copolymers in which a silicone macromer such aspolydimethylsiloxane having a methacryl group in the terminal is addedin order to obtain high oxygen permeability and rubber elasticity. Forthis reason, when they are used as contact lenses, for example, thereare instances in which the contact lenses are turbid.

DISCLOSURE OF THE INVENTION

This invention has the objective of providing monomers and polymers,ophthalmic lenses and contact lenses in which they are used, in whichthe polymers that are obtained by polymerization are of high oxygenpermeability and which have sufficient compatibility in three-componentsystems of silicone macromers/hydrophilic monomers.

In order to achieve the aforementioned objectives, this invention hasthe following structure.

(1) A monomer comprising a polymerizable unsaturated double bond andsiloxanyl group, wherein said monomer comprises a substituted groupcontaining an ester group in a side chain.

(2) The monomer of (1) above wherein the substituted group containing anester group has an ether bond and polyalkylene glycol chain.

(3) A monomer that is represented by general formula (a) or (a′) below:

wherein A is a siloxanyl group; R¹ is H or a methyl group; R² is asubstituted group that is selected from the group consisting of alkylgroups with 1 to 20 carbon atoms that may be substituted, aryl groupswith 6 to 20 carbon atoms that may be substituted and formula (c) below:

wherein in formula (c), R³ is H or a methyl group and R⁴ is asubstituted group that is selected from the group consisting of alkylgroups with 1 to 20 carbon atoms that may be substituted and aryl groupswith 6 to 20 carbon atoms that may be substituted; k indicates aninteger of 0 to 200.

-   -   (4) The monomer of (3) above wherein the siloxanyl group (A) in        formula (a) or (a′) is a substituted group as represented by        formula (b) below:

wherein in formula (b), A¹ to A¹¹, independently and respectively, areselected from H, alkyl groups of 1 to 20 carbon atoms that may besubstituted or aryl groups of 6 to 20 carbon atoms that may besubstituted; n indicates an integer of 0 to 200 and a, b and c,independently and respectively, indicate integers of 0 to 20, providedthat the case where all of n, a, b and c denote zero is to beeliminated.

(5) The monomer of (3) above wherein the siloxanyl group (A) in theaforementioned general formula (a) or (a′) is a substituted group thatis selected from tris(trimethylsiloxy)silyl groups,bis(trimethylsiloxy)methylsilyl groups and trimethylsiloxydimethylsilylgroups.

(6) A polymer comprising the monomer described in either of (1) or (3)above as a polymerization component.

(7) The polymer of (6) above wherein a ratio of the substituted groupcontaining an ester group and the siloxanyl group is 0.1 to 1.

(8) A polymer which is a homopolymer of the monomer described in either(1) or (3) above.

(9) A polymer comprising the monomer described in either (1) or (3)above in a range of 10% to 80% as a polymerization component.

(10) An ophthalmic lens which comprises the polymer described in (6)above.

(11) A contact lens which comprises the polymer described in (6) above.

EMBODIMENT OF THE INVENTION

First, we shall describe the various functional groups in the monomers.The polymerizable unsaturated double bond may be any double bond as longas it can produce polymers by radical polymerization. Examples of groupsthat can be used include (meth)acryloyl groups, styryl groups, benzoylgroups and vinyl groups. Of these, the use of methacryloyl groups isdesirable from the standpoints of ease of synthesis andpolymerizability.

The term siloxanyl group indicates a group that has at least one Si—O—Sibond. The use of substituted groups represented by formula (b) below asthe siloxanyl groups is desirable from the standpoints of ease ofacquisition of raw materials and ease of synthesis.

[In formula (b), A¹ to A¹¹, independently and respectively, indicate H,alkyl groups of 1 to 20 carbon atoms that may be substituted or arylgroups of 6 to 20 carbon atoms that may be substituted. n indicates aninteger of 0 to 200 and a, b and c, independently and respectively,indicate integers of 0 to 20, provided that the case where all of n, a,b and c denote zero is to be eliminated.]

The substituted groups having ester groups of this invention areintroduced to mitigate the water-repellency of the monomers of thisinvention and to increase their hydrophilic properties. In addition tosimple ester groups, substituted groups having polyalkylene glycolchains and ether bonds can be cited as desirable examples.

In order to further facilitate understanding of the nature of thisinvention, we shall now describe the various substituted groups ingeneral formula (a) or (a′) more specifically.

In formula (b), which illustrates the siloxanyl groups of A, A¹ to A¹¹,independently and respectively, indicate H, alkyl groups such as methylgroups, ethyl groups, propyl groups, isopropyl groups, butyl groups,isobutyl groups, sec-butyl groups, t-butyl groups, hexyl groups,cyclohexyl groups, 2-ethylhexyl groups and octyl groups and aryl groupssuch as phenyl groups and naphthyl groups. Examples of alkyl groups andaryl groups that may be substituted can include 3-glycidoxypropylgroups, 2-hydroxyethoxypropyl groups, 3-hydroxypropyl groups,3-aminopropyl groups and fluorophenyl groups. Of these, methyl groupsare the most desirable.

In formula (b), n is an integer of 0 to 200, preferably, of 0 to 50,and, more preferably, of 0 to 10. a, b and c are, respectively andindividually, integers of 0 to 20, and, preferably, a, b and c are,respectively and individually, integers of 0 to 5. When n=0, desirablecombinations of a, b and c are a=b=c=1, a=b=1 and c=0.

Of the substituted groups represented by formula (b), those that areparticularly desirable from the standpoint that they can acquiredindustrially comparatively cheaply are tris(trimethylsiloxy)silylgroups, bis(trimethylsiloxy)methylsilyl groups,trimethylsilyoxydimethylsilyl groups, polydimethylsiloxane groups,polymethylsiloxane groups and poly-co-methylsiloxane-dimethylsiloxanegroups.

In formula (a) or (a′), R² indicates substituted groups that areselected from the group consisting of alkyl groups of 1 to 20 carbonatoms that may be substituted, aryl groups of 6 to 20 carbon atoms thatmay be substituted and formula (c) below.

When R² is selected from the group consisting of alkyl groups of 1 to 20carbon atoms that may be substituted and aryl groups of 6 to 20 carbonatoms that may be substituted, desirable examples include methyl groups,ethyl groups, propyl groups, butyl groups, pentyl groups, hexyl groups,heptyl groups, octyl groups, decyl groups, cyclohexyl groups, benzylgroups, phenyl groups and naphthyl groups. Of these, methyl groups,ethyl groups and phenyl groups are preferable, and methyl groups aremost preferable. When R² is selected from a group comprised ofsubstituted groups of the form of formula (c), R⁴ in formula (c)indicates substituted groups that are selected from the group consistingof alkyl groups of 1 to 20 carbon atoms that may be substituted and arylgroups of 6 to 20 carbon atoms that may be substituted. Desirableexamples include methyl groups, ethyl groups, propyl groups, butylgroups, pentyl groups, hexyl groups, heptyl groups, octyl groups, decylgroups, cyclohexyl groups, benzyl groups, phenyl groups and naphthylgroups. Of these, methyl groups, ethyl groups and phenyl groups arepreferable, and methyl groups are most preferable.

In formula (c), k indicates an integer of 0 to 200. When k increases,the hydrophilic property becomes stronger. However, the balance withhigh oxygen permeability deteriorates, for which reason it should be 0to 50, and, more preferably, 0 to 20, in order to obtain a good balanceof physical properties.

The polymers of this invention can be obtained by polymerizing themonomers of this invention individually and they can also be obtained bycopolymerization with other monomers. There are no particularlimitations on the other monomers that are copolymerized as long as theycan be copolymerized, and monomers that have (meth)acryloyl groups,styryl groups, allyl groups, vinyl groups and other polymerizablecarbon-carbon unsaturated bonds can be utilized.

Several examples are presented below. However, this invention is notlimited to them. One group of examples includes a hydrophilic monomergroup comprised of (meth)acrylic acid, itaconic acid, crotonic acid,vinyl benzoic acid, (meth)acrylamides such as N,N-dimethylacrylamide andN-vinyl lactams such as N-vinyl pyrrolidone. Another group of examplesis a hydrophobic monomer group including alkyl (meth)acrylates such asmethyl (meth)acrylate and aromatic vinyl monomers such as styrene.Further, monomers having oxygen permeability include (meth)acrylatescontaining fluoroalkyl groups, silicone macromers such aspolydimethylsiloxane having (meth)acryloyl groups in the terminals and3-[tris(trimethylsiloxy)silyl]propylmethacrylate.

The (co)polymerization ratio of monomers represented by general formula(a) or (a′) in the polymers of this invention, in the case in which theydo not include monomers containing silicon groups and from thestandpoint of establishing both high oxygen permeability and highhydrophilic properties, should be 30 to 100 weight %, preferably, 40 to99 weight %, and, more preferably, 50 to 95 weight %.

In copolymerization with oxygen permeable monomers, it is desirable thatthe total for the monomers of this invention and other oxygen permeablemonomers be within the range of the aforementioned copolymerizationratio. Further, in this case, when the proportion of siloxanyl groups isexcessively high, it is difficult to assure balance between wettabilityand oxygen permeability, for which reason, it is necessary to set aratio of the substituted group having ester groups and the siloxanylgroup in the polymer above a fixed value. That is, it is necessary thatit be from 0.1 to 1. Values from 0.3 to 0.7 are particularly desirable.

For the purpose of obtaining good mechanical properties and of obtaininggood resistance to disinfecting solutions and cleaning solutions, it isdesirable to use monomers having two or more copolymerizablecarbon-carbon unsaturated bonds in one molecule, in the polymers of thisinvention. The copolymerization ratio of the monomers having two or morecopolymerizable carbon-carbon unsaturated bonds in one molecule shouldbe greater than 0.1 weight %, preferably, greater than 0.3 weight %,and, more preferably, greater than 0.5 weight %.

The polymer of this invention may also contain ultraviolet absorbents,pigments and colorants. It may also contain ultraviolet absorbents,pigments and colorants having polymerizable groups in the form that theyare copolymerized.

In order to facilitate polymerization when the polymers of thisinvention are obtained by polymerization, the addition of thermalpolymerization initiators and photopolymerization initiators of whichperoxides and azo compounds are representative is desirable. Whenthermal polymerization is performed, a substance having optimumdecomposition characteristics at the desired reaction temperature isselected and used. In general, azo initiators and peroxide initiatorshaving 10 hour half-life temperatures of 40° C. to 120° C. are suitable.Carbonyl compounds, peroxides, azo compounds, sulfur compounds, halogencompounds and metal salts can be cited as photopolymerizationinitiators. These polymerization initiators can be used individually orin mixtures and are used in quantities up to approximately 1 weight %.

A polymerization solvent can be used when the polymers of this inventionare obtained by polymerization. Various organic and inorganic solventscan be used as the solvents and there are no particular limitations onthem. Examples that can be cited include water, various alcohol solventssuch as methanol, ethanol, propanol, 2-propanol, butanol andtert-butanol, various aromatic hydrocarbon solvents such as benzene,toluene and xylene, various aliphatic hydrocarbon solvents such ashexane, heptane, octane, decane, petroleum ether, kerosene, ligroin andparaffin, various ketone solvents such as acetone, methyl ethyl ketoneand methyl isobutyl ketone, various ester solvents such as ethylacetate, butyl acetate, methyl benzoate, dioctyl plithalate and ethyleneglycol diacetate and various glycol ether solvents such as diethylether, tetrahydrofuran, dioxane, ethylene glycol dialkyl ethers,diethylene glycol dialkyl ethers, triethylene glycol dialkyl ethers,tetraethylene glycol dialkyl ethers and polyethylene glycol dialkylethers. They can be used individually or in mixtures.

Usual methods can be used as the polymerization methods and moldingmethods of the polymers of this invention. They include, for example, amethod in which they are molded into rods or plates and are thenprocessed to the desired shapes by cutting and processing, a moldpolymerization method and a spin cast method. As an example, we shallnow describe the case in which the polymer of this invention is obtainedby the mold polymerization method.

The monomer composition is filled into the space of two molds having afixed shape. Photopolymerization or thermal polymerization is performedand it is formed to the shape of the mold. The mold can be made ofresin, glass, ceramics or metal. In the case of photopolymerization, amaterial that is optically transparent is used, and, ordinarily, resinor glass is used. In many cases, when a polymer is manufactured, a spaceis formed by the two opposing molds and the space is filled with themonomer composition. Depending on the shape of the mold and theproperties of the monomer, a gasket may be used for the purpose ofconferring a fixed thickness on the polymer and of preventing leakage ofthe filled monomer composition solution. The mold into the space ofwhich the monomer composition is filled is then irradiated with activelight rays such as ultraviolet rays or is introduced into an oven or awater bath or oil bath and is heated to polymerize the monomers. The twomethods can also be used in combination, with thermal polymerizationbeing performed after photopolymerization, or, conversely, it can bephotopolymerization being performed after thermal polymerization. In thecase of photopolymerization, for example, light containing a largeportion of ultraviolet rays is usually irradiated for a short time(ordinarily 1 hour or less) using a mercury lamp or an insect attractionlamp as the light source. When thermal polymerization is performed, thetemperature is gradually raised from close to room temperature, beingincreased to a temperature of 60° C. to 200° C. over a period of severalhours to several tens of hours. These conditions are desirable for thepurpose of maintaining the optical homogeneity and quality of thepolymer and of increasing reproducibility.

The molded product in which the polymer of this invention is used can besubjected to modification treatments by various methods. It is desirableto perform said modification treatment for the purpose of increasingsurface wettability.

Specific modification methods can include electromagnetic wave(including light) irradiation, plasma irradiation, chemical vapordeposition treatments such as vaporization and sputtering, heatingtreatments, treatment with bases, treatment with acids and the use ofother suitable surface treatment agents, and combinations of thesetreatments. Of these modification procedures, treatment with bases andtreatment with acids are desirable because they are simple.

Examples of treatments with bases and treatments with acids that can becited include a method in which the molded product is brought intocontact with a basic or acidic solution and a method in which the moldedproduct is brought into contact with a basic or acidic gas. Morespecific examples include, for example, a method in which the moldedproduct is immersed in a basic or acidic solution, a method in which abasic or acidic solution or basic or acidic gas is sprayed onto themolded product, a method in which the basic or acidic solution isapplied to the molded product with a spatula or brush and a method inwhich the basic or acidic solution is applied to the molded product by aspin coating method or a dip coating method. The method whereby greatmodifying effects can be obtained the most simply is the method in whichthe molded product is immersed in a basic or acidic solution.

There are no particular limitations on the temperature when the moldedproduct is immersed in the basic or acidic solution. However, theprocedure is usually performed in a temperature range of −50° C. to 300°C. When workability is considered, a temperature range of −10° C. to150° C. is preferable and −5° C. to 60° C. is more preferable.

The optimum period for immersion of the molded product in the basic oracidic solution varies depending on the temperature. In general, aperiod of up to 100 hours is desirable, a period of up to 24 hours ismore preferable and a period of up to 12 hours is most preferable. Whencontact time is too long, workability and productivity deteriorate andthere are instances in which there are such deleterious effects asdecrease of oxygen permeability and decrease of mechanical properties.

The bases that can be used include alkali metal hydroxides, alkalineearth metal hydroxides, various carbonates, various borates, variousphosphates, ammonia, various ammonium salts, various amines and highmolecular weight bases such as polyethylene imines and polyvinyl amines.Of these, alkali metal hydroxides are the most desirable because oftheir low cost and their great treatment effectiveness.

The acids that can be used include various inorganic acids such assulfuric acid, phosphoric acid, hydrochloric acid and nitric acid,various organic acids such as acetic acid, formic acid, benzoic acid andphenol and various high molecular weight acids such as polyacrylic acidsand polystyrene sulfonic acids. Of these, high molecular weight acidsare the most desirable because they have great treatment effectivenessand have little deleterious effect on other physical properties.

Various inorganic and organic solvents can be used as solvents of thebasic and acidic solutions. For example, they can include water, variousalcohols such as methanol, ethanol, propanol, 2-propanol, butanol,ethylene glycol, diethylene glycol, triethylene glycol, tetraethyleneglycol, polyethylene glycol and glycerol, various aromatic hydrocarbonssuch as benzene, toluene and xylene, various aliphatic hydrocarbons suchas hexane, heptane, octane, decane, petroleum ether, kerosene, ligroinand paraffin, various ketones such as acetone, methyl ethyl ketone andmethyl isobutyl ketone, various esters such as ethyl acetate, butylacetate, methyl benzoate and dioctyl phthalate, various ethers such asdiethyl ether, tetrahydrofuran, dioxane, ethylene glycol dialkyl ether,diethylene glycol dialkyl ether, triethylene glycol dialkyl ether,tetraethylene glycol dialkyl ether and polyethylene glycol dialkylether, various nonprotonic polar solvents such as dimethylformamide,dimethylacetamide, N-methyl-2-pyrrolidone, dimethylimidazolidinone,hexamethyl phosphoric triamide and dimethyl sulfoxide, halogen solventssuch as methylene chloride, chloroform, dichloroethane, trichloroethaneand trichloroethylene and freon solvents. Of these, water is the mostdesirable from the standpoints of economic factors, convenience ofhandling and chemical stability. These solvents can also be used inmixtures of two or more.

The basic or acidic solution that is used in this invention may alsocontain components other than the basic or acidic substances and thesolvents.

After the molded product has been subjected to treatment with bases oracids, the basic or acidic substance can be removed by washing.

Various inorganic and organic solvents can be used as washing solvents.For example, they can include water, various alcohols such as methanol,ethanol, propanol, 2-propanol, butanol, ethylene glycol, diethyleneglycol, triethylene glycol, tetraethylene glycol, polyethylene glycoland glycerol, various aromatic hydrocarbons such as benzene, toluene andxylene, various aliphatic hydrocarbons such as hexane, heptane, octane,decane, petroleum ether, kerosene, ligroin and paraffin, various ketonessuch as acetone, methyl ethyl ketone and methyl isobutyl ketone, variousesters such as ethyl acetate, butyl acetate, methyl benzoate and dioctylphthalate, various ethers such as diethyl ether, tetrahydrofuran,dioxane, ethylene glycol dialkyl ether, diethylene glycol dialkyl ether,triethylene glycol dialkyl ether, tetraethylene glycol dialkyl ether andpolyethylene glycol dialkyl ether, various nonprotonic polar solventssuch as dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone,dimethylimidazolidinone, hexamethyl phosphoric triaminde and dimethylsulfoxide, halogen solvents such as methylene chloride, chloroform,dichloroethane, trichloroethane and trichloroethylene and freonsolvents.

Mixtures of two or more of these solvents can be used as the washingsolvent. The washing solvent may contain components other than thesolvents, for example, inorganic salts, surfactants and detergents.

The entire molded product may be subjected to said modificationtreatment or it may be performed on only a portion of the moldedproduct, for example, the surface. When only the surface is subjected tomodification treatment, only the aqueous wetting property of the surfacecan be improved without making great changes in the physical propertiesof the molded product as a whole.

The polymers of this invention should have an oxygen permeabilitycoefficient greater than 70×10⁻¹¹ (cm²/sec)mLO₂/(mL·hPa) in terms of theoxygen permeability.

The polymers of this invention are particularly suited for ophthalmiclenses such as contact lenses, intraocular lenses and artificialcorneas.

EXAMPLES

We shall now describe this invention in specific terms by means ofexamples. However, this invention is not limited by them.

Determination Methods

The various determinations in these examples were performed by themethods described below.

(1) Proton Nuclear Magnetic Resonance Spectrum

Determinations were performed using a model EX270 manufactured by JEOLLtd. Chloroform-d was used as the solvent.

(2) Gas Chromatography (GC)

A capillary column (TC-5HT) manufactured by GL Sciences, Inc. was usedwith a model GC-18A manufactured by SHIMADZU CORPORATION. Determinationswere made with a temperature elevation program in which the temperaturewas maintained at 100° C. for 1 minute, after which the temperature wasraised to 340° C. at a rate of 10° C./minute and then maintained at 340°C. for 5 minutes (introduction inlet temperature, 340° C.; detectiontemperature, 360° C.). Helium was used as a carrier gas.

(3) Oxygen Permeability Coefficient

The oxygen permeability coefficient of a sample in the shape of acontact lens was determined in water of 35° C. using a Seikaken-shikifilm oxygen permeability meter manufactured by RIKA SEIKI KOGYO Co.,Ltd.

Example 1

40 mg (95 mmol) of a siloxanyl monomer mixture represented by formulas(d) and (d′) below:

synthesized by a method in which methacrylic acid and3-glycidoxypropylmethylbis(trimethylsiloxy)silane were reacted usingsodium methacrylate as the catalyst as described in Japanese PatentApplication Laid-Open No. 22325/1981, 14.36 g (142 mmol) oftriethylamine and 80 ml of ethyl acetate were added to a 200 mL eggplanttype distillation flask and 10.1 ml (142 mmol) of acetyl chloride wasadded dropwise at 0° C. as the mixture was being stirred. The reactionsolution was stirred for 2 hours at room temperature, after which theprecipitate was removed by filtration and ethyl acetate was added. Itwas then washed twice with a saturated sodium hydrogencarbonate solutionand once with saturated saline solution and dried with sodium sulfate.The solvent was removed with an evaporator and the liquid that wasobtained was purified by distillation under reduced pressure, and atransparent liquid was obtained. Two peaks (peak area ratio, 82/18) wereseen on the GC of the liquid that was obtained. When the molecularweights of the compounds comprising the peaks were found by GC-MS, itwas indicated that the molecular weights of the compounds comprisingthese peaks were the same. For this reason, it was confirmed that thecompounds comprising these peaks were isomers of each other. The protonnuclear magnetic resonance spectrum of the liquid was determined andanalyzed. As a result, peaks were detected in the vicinity of 0 ppm(3H), in the vicinity of 0.1 ppm (18H), in the vicinity of 0.4 ppm (2H),in the vicinity of 1.5 ppm (2H), in the vicinity of 1.9 ppm (3H), in thevicinity of 2.1 ppm (3H), in the vicinity of 3.4 ppm (1H), in thevicinity of 3.6 ppm (2H), in the vicinity of 4.2 ppm (1H), in thevicinity of 4.4 ppm (1H), in the vicinity of 5.2 ppm (1H), in thevicinity of 5.6 ppm (1H) and in the vicinity of 6.1 ppm (1H). From thesefindings, it was concluded that it was a mixture of the compoundsrepresented by formulas (M1) and (M1′) below.

Example 2

Synthesis was performed in the same way as in Example 1 using asiloxanyl monomer mixture represented by formulas (e) and (e′) below,instead of the siloxanyl monomer mixture (d) and (d′),

synthesized by a method in which methacrylic acid and3-glycidoxypropyltris(trimethylsiloxy)silane were reacted using sodiummethacrylate as the catalyst as described in Japanese Patent ApplicationLaid-Open No. 22325/1981. The proton nuclear magnetic resonance spectrumof the liquid that was obtained was determined and analyzed. As aresult, peaks were detected in the vicinity of 0.1 ppm (27H), in thevicinity of 0.4 ppm (2H), in the vicinity of 1.5 ppm (2H), in thevicinity of 1.9 ppm (3H), in the vicinity of 2.1 ppm (3H), in thevicinity of 3.4 ppm (1H), in the vicinity of 3.6 ppm (2H), in thevicinity of 4.2 ppm (1H), in the vicinity of 4.4 ppm (1H), in thevicinity of 5.2 ppm (1H), in the vicinity of 5.6 ppm (1H) and in thevicinity of 6.1 ppm (1H). From these findings, it was concluded that itwas a mixture of the compounds represented by formulas (M2) and (M2′)below. The GC peak area ratio of this mixture was 87/13.

Example 3

Synthesis was performed in the same way as in Example 1 using propionylchloride instead of acetyl chloride. The proton nuclear magneticresonance spectrum of the liquid that was obtained was determined andanalyzed. As a result, peaks were detected in the vicinity of 0 ppm(3H), in the vicinity of 0.1 ppm (18H), in the vicinity of 0.4 ppm (2H),in the vicinity of 1.1 ppm (3H), in the vicinity of 1.5 ppm (2H), in thevicinity of 1.9 ppm (3H), in the vicinity of 2.3 ppm (2H), in thevicinity of 3.4 ppm (1H), in the vicinity of 3.6 ppm (2H), in thevicinity of 4.2 ppm (1H), in the vicinity of 4.4 ppm (1H), in thevicinity of 5.2 ppm (1H), in the vicinity of 5.6 ppm (1H) and in thevicinity of 6.1 ppm (1H). From these findings, it was concluded that itwas a mixture of the compounds represented by formulas (M3) and (M3′)below. The GC peak area ratio of this mixture was 84/16.

Example 4

Synthesis was performed in the same way as in Example 2 using propionylchloride instead of acetyl chloride. The proton nuclear magneticresonance spectrum of the liquid that was obtained was determined andanalyzed. As a result, peaks were detected in the vicinity of 0.1 ppm(27H), in the vicinity of 0.4 ppm (2H), in the vicinity of 1.1 ppm (3H),in the vicinity of 1.5 ppm (2H), in the vicinity of 1.9 ppm (3H), in thevicinity of 2.3 ppm (2H), in the vicinity of 3.4 ppm (1H), in thevicinity of 3.6 ppm (2H), in the vicinity of 4.2 ppm (1H), in thevicinity of 4.4 ppm (1H), in the vicinity of 5.2 ppm (1H), in thevicinity of 5.6 ppm (1H) and in the vicinity of 6.1 ppm (1H). From thesefindings, it was concluded that it was a mixture of the compoundsrepresented by formulas (M4) and (M4′) below. The GC peak area ratio ofthis mixture was 86/14.

Example 5

Synthesis was performed in the same way as in Example 1 using butyrylchloride instead of acetyl chloride. The proton nuclear magneticresonance spectrum of the liquid that was obtained was determined andanalyzed. As a result, peaks were detected in the vicinity of 0 ppm(3H), in the vicinity of 0.1 ppm (18H), in the vicinity of 0.4 ppm (2H),in the vicinity of 0.9 ppm (3H), in the vicinity of 1.5 ppm (2H), in thevicinity of 1.7 ppm (2H), in the vicinity of 1.9 ppm (3H), in thevicinity of 2.3 ppm (2H), in the vicinity of 3.4 ppm (1H), in thevicinity of 3.6 ppm (2H), in the vicinity of 4.2 ppm (1H), in thevicinity of 4.4 ppm (1H), in the vicinity of 5.2 ppm (1H), in thevicinity of 5.6 ppm (1H) and in the vicinity of 6.1 ppm (1H). From thesefindings, it was concluded that it was a mixture of the compoundsrepresented by formulas (M5) and (M5′) below. The GC peak area ratio ofthis mixture was 85/15.

Example 6

Synthesis was performed in the same way as in Example 2 using butyrylchloride instead of acetyl chloride. The proton nuclear magneticresonance spectrum of the liquid that was obtained was determined andanalyzed. As a result, peaks were detected in the vicinity of 0.1 ppm(27H), in the vicinity of 0.4 ppm (2H), in the vicinity of 0.9 ppm (3H),in the vicinity of 1.5 ppm (2H), in the vicinity of 1.7 ppm (2H), in thevicinity of 1.9 ppm (3H), in the vicinity of 2.3 ppm (2H), in thevicinity of 3.4 ppm (1H), in the vicinity of 3.6 ppm (2H), in thevicinity of 4.2 ppm (1H), in the vicinity of 4.4 ppm (1H), in thevicinity of 5.2 ppm (1H), in the vicinity of 5.6 ppm (1H) and in thevicinity of 6.1 ppm (1H). From these findings, it was concluded that itwas a mixture of the compounds represented by formulas (M6) and (M6′)below. The GC peak area ratio of this mixture was 85/15.

Examples 7

Synthesis was performed in the same way as in Example 1 usingmethoxyacetyl chloride instead of acetyl chloride. The proton nuclearmagnetic resonance spectrum of the liquid that was obtained wasdetermined and analyzed. As a result, peaks were detected in thevicinity of 0 ppm (3H), in the vicinity of 0.1 ppm (18H), in thevicinity of 0.4 ppm (2H), in the vicinity of 1.5 ppm (2H), in thevicinity of 1.9 ppm (3H), in the vicinity of 3.4 ppm (4H), in thevicinity of 3.6 ppm (2H), in the vicinity of 4.0 ppm (2H), in thevicinity of 4.2 ppm (1H), in the vicinity of 4.4 ppm (1H), in thevicinity of 5.2 ppm (1H), in the vicinity of 5.6 ppm (1H) and in thevicinity of 6.1 ppm (1H). From these findings, it was concluded that itwas a mixture of the compounds represented by formulas (M7) and (M7′)below. The GC peak area ratio of this mixture was 83/17.

Example 8

Synthesis was performed in the same way as in Example 2 usingmethoxyacetyl chloride instead of acetyl chloride. The proton nuclearmagnetic resonance spectrum of the liquid that was obtained wasdetermined and analyzed. As a result, peaks were detected in thevicinity of 0.1 ppm (27H), in the vicinity of 0.4 ppm (2H), in thevicinity of 1.5 ppm (2H), in the vicinity of 1.9 ppm (3H), in thevicinity of 3.4 ppm (4H), in the vicinity of 3.6 ppm (2H), in thevicinity of 4.0 ppm (2H), in the vicinity of 4.2 ppm (1H), in thevicinity of 4.4 ppm (1H), in the vicinity of 5.2 ppm (1H), in thevicinity of 5.6 ppm (1H) and in the vicinity of 6.1 ppm (1H). From thesefindings, it was concluded that it was a mixture of the compoundsrepresented by formulas (M8) and (M8′) below. The GC peak area ratio ofthis mixture was 87/13.

Example 9

Synthesis was performed in the same way as in Example 1 using asiloxanyl monomer mixture represented by formulas (f) and (f) below,instead of the siloxanyl monomer mixture (d) and (d′),

that was synthesized using acrylic acid and sodium acrylate instead ofmethacrylic acid and sodium methacrylate by a method in whichmethacrylic acid and 3-glycidoxypropylmethylbis(trimethylsiloxy)silanewere reacted using sodium methacrylate as the catalyst as described inJapanese Patent Application Laid-Open No. 22325/1981. The proton nuclearmagnetic resonance spectrum of the liquid that was obtained wasdetermined and analyzed. As a result, peaks were detected in thevicinity of 0.1 ppm (27H), in the vicinity of 0.4 ppm (2H), in thevicinity of 1.5 ppm (2H), in the vicinity of 1.9 ppm (3H), in thevicinity of 2.1 ppm (3H), in the vicinity of 3.4 ppm (1H), in thevicinity of 3.6 ppm (2H), in the vicinity of 4.2 ppm (1H), in thevicinity of 4.4 ppm (1H), in the vicinity of 5.2 ppm (1H), in thevicinity of 5.6 ppm (1H), in the vicinity of 6.1 ppm (1H) and in thevicinity of 6.4 ppm (1H). From these findings, it was concluded that itwas a mixture of the compounds represented by formulas (M9) and (M9′)below. The GC peak area ratio of this mixture was 85/15.

Example 10

The mixture of compounds of formulas (M1) and (M1′) obtained in Example1 (30 parts by weight), N,N-dimethylacrylamide (40 parts by weight),polydimethylsiloxane of which the terminals had been methacrylated(molecular weight, approximately 1,000; 30 parts by weight), triethyleneglycol dimethacrylate (1 part by weight) and Darocure 1173 (CIBASpecialty Chemicals Inc.; 0.2 part by weight) were mixed and stirred. Ahomogeneous and transparent monomer mixture was obtained. This monomermixture was deaerated in an argon atmosphere. It was poured into acontact lens mold made of a transparent resin (poly 4-methylpentene-1)in a glove box in a nitrogen atmosphere and was polymerized by lightirradiation (1 mW/cm², 10 minutes) using an insect attraction lamp, anda sample in the shape of a contact lens was obtained.

The lens-shaped sample that was obtained was subjected to hydrationtreatment, after which it was immersed in a 5 weight % aqueous solutionof polyacrylic acid (molecular weight, approximately 150,000) andmodification treatment was performed for 8 hours at 40° C. After themodification treatment, it was washed thoroughly with purified water andimmersed in a boric acid buffer solution (pH 7.1 to 7.3) in a vial andthe vial was hermetically sealed. Said vial was introduced into anautoclave and boiling treatment was performed for 30 minutes at 120° C.After it had cooled, the lens-shaped sample was removed from the vialand was immersed in a boric acid buffer solution (pH 7.1 to 7.3).

The sample that was obtained was transparent and not turbid. When thissample was subjected to hydration treatment, its oxygen permeabilitycoefficient was 79×10⁻¹¹ (cm²/sec)mLO₂/(mL·hPa). Thus, it had hightransparency and high oxygen permeability.

Examples 11 to 18

The monomer mixtures obtained in Examples 2 to 9 were used and contactlens-shaped samples were obtained by the same method as in Example 10.All of the samples that were obtained were transparent and not turbid.The oxygen permeability coefficients [×10 ⁻¹¹ (cm²/sec)mLO₂/(mL·hPa)]when these samples were subjected to hydration treatment are shown inTable 1 below. All of the polymers were of high transparency and oxygenpermeability.

TABLE 1 Oxygen permeability coefficient [×10⁻¹¹ (cm²/sec)mLO₂/(mL ·hPa)] Example 11 107 Example 12 78 Example 13 108 Example 14 78 Example15 104 Example 16 75 Example 17 105 Example 18 80

Comparative Examples

When a monomer mixture was prepared at the same molar ratio as inExample 10 using 3-tris(trimethylsiloxy)silylpropyl methacrylate, thesubstances did not mix sufficiently and separated from each other. Thismonomer mixture was polymerized by light irradiation in the same way asin Example 10, but a transparent contact lens-shaped sample was notobtained.

INDUSTRIAL APPLICABILITY

By means of this invention, monomers are provided so that the polymersthat are obtained by polymerization are of high oxygen permeability andtransparency.

1. A monomer that is represented by general formula (a) or (a′) below:

wherein A is a siloxanyl group; R¹ is H or a methyl group; R² is asubstituted group that is selected from the group consisting of alkylgroups with 1 to 20 carbon atoms that may be substituted, aryl groupswith 6 to 20 carbon atoms that may be substituted and formula (c) below:

wherein, in formula (c), R³ is H or a methyl group and R⁴ is asubstituted group that is selected from the group consisting of alkylgroups with 1 to 20 carbon atoms that may be substituted and aryl groupswith 6 to 20 carbon atoms that may be substituted; k indicates aninteger of 0 to
 200. 2. The monomer of claim 1 wherein the siloxanylgroup (A) in formula (a) or (a′) is a substituted group as representedby formula (b) below:

wherein, in formula (b), A¹ to A¹¹, independently and respectively, areselected from H, alkyl groups of 1 to 20 carbon atoms that may besubstituted or aryl groups of 6 to 20 carbon atoms that may besubstituted; n indicates an integer of 0 to 200 and a, b and c,independently and respectively, indicate integers of 0 to 20; providedthat the case where all of n, a, b and c denote zero is to beeliminated.
 3. The monomer of claim 1 wherein the siloxanyl group (A) inthe aforementioned general formula (a) or (a′) is a substituted groupthat is selected from tris(trimethylsiloxy)silyl groups,bis(trimethylsiloxy)methylsilyl groups and trimethylsiloxydimethylsilylgroups.
 4. A polymer comprising the monomer set forth in either of claim1 as a polymerization component.
 5. The polymer of claim 4 in which aratio of the substituted group having an ester group and the siloxanylgroup is 0.1 to
 1. 6. A polymer which is a homopolymer of the monomerset forth in claim
 1. 7. A polymer comprising the monomer set forth inclaim 1 in a range of 10% to 80% as a polymerization component.
 8. Anophthalmic lens which comprises the polymer set forth in claim
 4. 9. Acontact lens which comprises the polymer set forth in claim 4.